In modern computers, local disk Input/Output (I/O) is often a bottleneck in the execution of a program when the processor blocked waiting for I/O access to read program files that are used to continue execution. In such cases, the processor may not be fully utilized. From the user perspective, this problem translates to long loading times. These delays are especially noticeable when several programs are starting simultaneously during boot-up.
Some current solutions include: using higher performance disk drives and using Redundant Array of Independent Disks (RAID) controllers for parallel access. These solutions require expensive hardware and a high level of technical expertise to implement.